Driver seat airbag device

Abstract

A driver seat airbag device that includes an occupant side panel of a cushion having a larger surface area than that of a steering wheel side panel and a side surface panel that forms the side surface of the cushion; the occupant side panel includes a depressed section recessed toward the steering wheel side and a bulged section in a ring shape positioned surrounding the depressed section; where based on prescribed means pulling toward the steering wheel side, a center area closest to the steering wheel and a first inclined area sloped in a flared shaped from the center area toward the occupant side are formed in the depressed section and a second inclined area continuous with the first inclined area is formed in the bulged section; and the center area and first and second inclined areas restrain the head of the occupant.

The invention claimed is: 
     
       1. A driver seat airbag device, comprising:
 an inflator stowed in a steering wheel of a vehicle; and 
 a cushion stowed in the steering wheel with the inflator that uses gas supplied from the inflator to expand and deploy, the cushion configured to deploy between the steering wheel and an occupant in a driver seat; wherein 
 the cushion includes:
 a steering wheel side panel positioned on a steering wheel side, 
 an occupant side panel having a larger surface area than the steering wheel side panel positioned on an occupant side, and 
 a side surface panel that connects the steering wheel side panel and the occupant side panel and forms a side surface of the cushion; 
 the occupant side panel includes:
 a depressed section recessed towards the steering wheel side, and 
 a bulged section positioned surrounding the depressed section that bulges in a ring shape toward the occupant side; where 
 a prescribed location of the occupant side panel is pulled to the steering wheel side by tethers including:
 a pair of main tethers positioned inside the cushion that span between the steering wheel side panel and the occupant side panel and have dimensions such that upon being tensioned during expansion and deployment of the cushion, pull the occupant side panel toward the steering wheel side, and 
 a pair of sub tethers positioned inside the cushion that span between a mid-section of the pair of main tethers and the occupant side panel and have dimensions such that upon being tensioned during expansion and deployment of the cushion, pull the occupant side panel toward the mid-section of the pair of main tethers; where 
 the pair of main tethers are separated and connected to edges of the depressed section of the occupant side panel; 
 the pair of sub tethers are separated and connected from the mid-section of the pair of main tethers to an inside of an edge of the depressed section such that the depressed section forms a center area closest to the steering wheel and a first inclined area inclined in a flared shape from the center area toward the occupant side and the bulged section forms a second inclined area that is continuous with the first inclined area and is inclined in a flared shape toward the occupant side; and 
 
 
 
 the cushion is configured to restrain a head of the occupant with the center area and the first and second inclined areas. 
 
     
     
       2. The driver seat airbag device according to  claim 1 , wherein the center area of the depressed section is positioned on a rotation axis of the steering wheel. 
     
     
       3. The driver seat airbag device according to  claim 1 , wherein when the depressed section is viewed from the occupant side toward the steering wheel side the depressed section has a vertically symmetrical and laterally symmetrical shape. 
     
     
       4. The driver seat airbag device according to  claim 3 , wherein the shape of the depressed section is such that when viewed from the occupant side toward the steering wheel side, a first dimension in a vertical direction and a second dimension in a lateral direction are the same. 
     
     
       5. The driver seat airbag device according to  claim 3 , wherein the shape of the depressed section is such that when viewed from the occupant side toward the steering wheel side, a first dimension in a vertical direction is longer than a second dimension in a lateral direction. 
     
     
       6. The driver seat airbag device according to  claim 3 , wherein the shape of the depressed section is such that when viewed from the occupant side toward the steering wheel side, a first dimension in a vertical direction is shorter than a second dimension in a lateral direction. 
     
     
       7. The driver seat airbag device according to  claim 1 , wherein a perpendicular line that perpendicularly intersects the first or second inclined area of the occupant side panel of the cushion intersects with the side surface panel. 
     
     
       8. A driver seat airbag device according to  claim 1 , wherein
 a dimension from the mid-section of the pair of main tethers to the occupant side panel is longer than a dimension of the pair of sub tethers. 
 
     
     
       9. The driver seat airbag device according to  claim 1 , wherein a width of the pair of main tethers is wider than a width of the pair of sub tethers. 
     
     
       10. The driver seat airbag device according to  claim 1 , wherein at least one of the pair of main tethers and the pair of sub tethers are provided lined up in a width direction of the vehicle or a vertical direction of the vehicle. 
     
     
       11. The driver seat airbag device according to  claim 1 , wherein the first and second inclined areas are sloped at an angle of 10° or more relative to a reference plane that is orthogonal to a rotation axis of the steering wheel.